1. Field of the Invention
The present invention relates to a lighting unit and a vehicular lighting apparatus.
2. Related Art
A lighting unit described in JP-A-2010-135076 has a pair of reflectors respectively having openings, and the reflectors are disposed at upper and lower positions on both sides of an optical axis of a projection lens so as to face each other. LED devices are disposed in the respective openings of the reflectors. The LED devices are disposed in the upper and lower reflectors which are positioned on both sides of the optical axis of the lighting unit so as to face each other, so that light that is radiated therefrom is reflected by the respective reflectors and projected onto a projection lens disposed in a front side.
This configuration makes it possible to guide an optical flux from the LED devices which are disposed up and down toward the projection lens without losses. In addition, since the LED devices are disposed up and down and spaced apart from each other, it is scarce that these devices are thermally influenced by each other when they generate heat. Accordingly, it is possible to reduce the influence of heat to the value of light flux of the LED devices.
When the lighting unit of JP-A-2010-135076 is applied to a headlight of a vehicle, a light distribution pattern for entire irradiation and a light distribution pattern for a high beam may be formed using light reflected from the upper and lower reflectors. In order to form only a low beam, a part of the light distribution pattern for entire irradiation may be shielded by a means such as a shade. However, when the reflection light is simply shielded in this fashion, a utilization rate of a light flux is lowered.